Cong nghiep rung
DAC DIEM CAU TAO GO THUY TUNG Phan Thi Thien Thu
KS. Trudng Dai hoc Ldm nghiep TOM T A T
Bai bao gioi thieu cau lao tho dai, cau tao hien thong qua anh chup ba mat cat cua go Thiiy tiing (Glypiostrobiis pensilis) sinh trucmg a Dak LSk. Ket qua nghien ciiu cho thay go Thuy tiing co dac man vang nhat, loi mau xanh hoi xam; vong nam ro, go som g6 mufln phan biet, mau sac tuong doi dep, go co min thom ddc tnmg, quan bao co chilu dai trung binh (1.896,79 - 4.094,01) jim, duong kinh quan g6 som Uung binh 46,85 pm, go mupn 16,71 |im, vach mong, go co quan bao chiia nhua; tia go be, mat do it khoang 4-5 tia/ mm; g6 Thiiy tung la loai gd c6 tho min.
Tii khoa: CSu tao hien vi go, cau tao tho dai go, Thuy timg.
I. BAT VAN DE
Thuy tung hay Thdng nude (ten khoa hgc Glyptosirobus pensilis) la loai thuc vat duy nhat cdn tdn tai thugc chi Glyptosirobus. Day la loai dac hiru cua vung can nhiet ddi dong nam Trung Qudc, tu tay Phiic Kien tdi ddng nam Van Nam, va cung hien dien d mien Nam Viet Nam. Rieng d Ddk Lak cdn 2 quan the Thuy tung tu nhien duy nhat d Viet nam la d huyen la Ea H'leo va Krdng Nang, hien nay loai gd nay da dugc khoanh vung bao ve nghiem ngat. Thuy tiing thudc loai cay dang cd nguy CO hi tuyet chiing theo sach do muc do de doa Bac E theo [4], Gd Thuy timg thugc loai gd quy, khdng hi mdi mgt, khdng bi cong venh nut ne, cd mau vdi vien rat dep nen dugc ua chuong de xay lau dai, nha ciia, lam do my nghe, dd dung cao cap. Tuy nhien cac thdng tin ve dac diem cau tao, cijng nhu tinh chSt ca ly ve loai gd nay d Viet Nam cdn ban che.
De bd sung them dii lieu v6 dac dilm cSu tao ciia cac loai gd quy hiSm ciia Viet Nam, nham tao ca sd dCr lieu lam can cu cho cdng tac giam dinh gd, nghien cuu nay da ti6n hanh md ta dac diem cau tao thd dai va hien vi ciia gd Thiiy tung {Glyptosirobus pensilis) sinh trudng tai Dak Lik.
n . VAT LIEU, PHirONG PHAP NGfflEN CUtJ 2.L Vat lieu nghien ciru
Gd Thuy tiing {Glyptosirobus pensilis) 65
2.2. Phuong phap nghien cuu
• Gd Thuy tung lam thi nghiem dugc lay d phan gd trudng thanh, khdng khuyet tat, d vi tri each gdc 1,3 m.
• Tao mSu quan sat cau tao thd dai:
Gia cdng mau cd kich thudc 3 chieu: Dgc thd X xuygn tam x tiSp tuyen (12 x 6,5x1,5) cm, sau dd lam nhan 3 mat cat dam bao quan sat dugc cac dac diem dac thd dai cua gd.
• Mau diing de cat tieu ban hien vi la mot khdi lap phuong, vdi kich thudc thich moi chieu la 13 mm, mau phai dam bao cd du 3 mat cat (mat cat ngang, mat cat xuyen tam va mat cat tiep tuyen). De cd the khao sat dugc day du cac dac tnmg ve cau tao can lay mau d phan gd thanh thuc ma tranh phan non (phan gd sinh ra trong nhimg nam dSu), bdi vi phSn gd nay cd su bien dpng ldn ve dac diem cau tao.
Sau dd tien hanh lam mem gd bang each cbo mlu vao luge trong nude sdi tdi khi thau nude hoan toan (mlu chim han trong nude).
Sau khi mau da thau nude hoan toan, ngam mlu vao hon hgp glyxerin - cdn vdi li le 1:1 cho den khi cd the cat dugc tieu ban du mong de quan sat bang kinh hien vi quang hoc (tiiy timg loai gd ma thdi gian ngam khac nhau, khi mau da mem ta lay mau ra cat thir).
Tao tieu ban hien vi; khi mau da dugc hda mem, tidn hanh cat mlu -> rua sach -^ nhupm mau trong dung dich Safranine -^ rua cac lat cat qua cae nong dp cdn tir thap den cao (muc dich lam thoat boi nude) -> dua cac lat cSt vao tudi sinh tnrdng d Dak Lak.
118 TAP CHI KHOA HOC VA CONG NGHE LAM NGHIEP SO 4-2014
Cong nghiep rimg ngam trong Xylen ^ dan tieu ban -^ cudi
cung cac tieu ban dugc lam bdng sach bang cdn va dan mac.
Quan sat va chup anh ba mat c5t: Anh ba mat cat dugc chup tren kinh hi^n vi OPTIKA dien tir cd ph§n m6m "Optika Visison 3.3".
Phuong phap md ta ciu t?o theo [lAWA Committee (2004). lAWA list of microscopic features for softwood identification. lAWA Journal 25(l):l-70]
III. KET QUA NGHIEN CUtJ 3.1. Cau tao tho dai
Gd Thuy timg ed giac ldi phan biet, giac mau vang nhat, ldi mau xanh hoi xam. Vdng nam rd, gd sdm gd mudn phan biet.
• Te bao md mem xep dgc than eay khdng rd
• Tia kich thudc be < 0.1 mm, sd lugng trung binh 4-5 tia/mm
• Gd khdng cd cau tao tbanb Idp.
• Gd khdng cd ong dan nhua dgc
• Gd nang trung binh, ben. Thd gd nghieng, tucmg ddi min.
Anh cau tao thd dai 3 mat cat the hien trong binh 1.
gj
Mat cdt ngang Mdi cdt xuyen tdm Mat cdt tiep tuyin Hinh 1. Hinh dnh cdu tgo tho
3.2. Dac dilm cau tao hien vi
• Quan bao cd hinh da giac, quan bao gd mudn chiem ty le it, chieu dai quan bao 3.113,75 (1.896,79 - 4.094,01) ^m, b6 rdng quan bao 33,09 ( 22,08 - 49,41) (im; dudng kinh quan gd sdm hung binh 46,85 jim, gd mudn 16,71 ^m; Id thdng ngang cd vanh xep thanh mdt den hai hang (da so 1 hang) tren vach xuyen tam cua quan bao dgc, cd quan bao chua nhua.
• Tia gd Thuy bang sd lugng trung binh, khoang 4-5 tia/mm, chieu dai tia 205 (im
dgi ba mat cat gd Thuy tiing
thudng bien ddng trong khoang UO - 430 |im;
be rgng tia trung binh khoang 39,08, thudng bi6n ddng trong khoang 27,17 - 53,08 |4m; Ld thdng ngang trong viing giao giiia te bao md mem tia gd va quan bao dgc cd sd lugng 1 -2 Id trong mpt d.
• Te bao md mem xep dgc than cay khdng ro.
• Gd khdng cd dug dan nhua.
• Anh cau tao hien vi 3 mat cat the hien trong hinh 2.
Mat cdt ngang (xI20) Mat cdl xuyin tdm (\480) Mat cdl tiep tuyen (\I20) Hinh 2. Hinh dnh cdu tgo hien vi ba mat cdt gd Thuy tiing
TAP CHI KHOA HOC VA CONG NGHE LAM NGHIEP SO 4-2014 119
Cong nghiep rimg IV. KET LUAN
• Ket qua nghien cuu cau tao thd dai va hien vi cua gd Thuy tiing cho thay gd Thuy timg quan bao cd chieu dai trung binh, vach mdng, cd quan bao chiia nhua gd ed khdi lugng the tich trung binh, kich thudc tia be, thinh thoang cd quan bao chiia nhua do dd lam tang do ben tu nhien ciia gd, ddng thdi can chu y trong qua trinh sSy do cd chat chiia nd lam cho gd khd say nhung nd cClng lam tang dp ben tu nhien ciia gd.
• Phuong phap nghien ciiu nay gdp phan tirng budc hoan thien xay dung bd suu tap gd cay la kim ndi rieng va gd Viet Nam ndi chung.
TAI LIEU THAM KHAO
1. Vu Han (1964), Kien thdc ca bdn ve gd, Nxb Khoa hoc ky thuat. Ha Noi.
2. Nguyen Dinh Hung (1990), Nghien ciju cdu tao giai phau go mot so loin cay g6 o Viet Nam de dinh loEii theo cac dac diem cau tao tho dai va hien vi, Luan an tien sy khoa hoc, Vien khoa hpc lam nghiep
3 Le Xuan Tinh (1998), Khoa hgc gd, Nxb Nong nghiep. Ha Npi.
4. Sach do Viet Nam - phan II thuc vat, Nxb Khoa hpc tu nhien - Ha Noi 2007
5. Vien khoa hoc Lam nghiep Viet Nam (2009), At lat cdu tgo, tinh chal gd vd tre Viet Nam, Nxb Nong nghiep. Ha Noi.
6. Wheeler, E.A., P. Baas & P.E. Gasson (1989).
lAWA list of microscopic features for hardwood identification. lAWA Bulletin n s 10(3). 219-332
WOOD ANATOMY OF Glyptosirobus pensilis
Phan Thi Thien Thu
SUMMARY
This smdy descnbres the macroscopic and microscopic features of the wood of Glyptosirobus pensilis originating from namral plants in Dak Lak province, Vietnam Results showed that sapwood pale yellow color, heanwood green to grey; growth rings distinct, transition from earlywood to latewood abrupt; wood with distinctive odor Tracheids medium m length, thin walls. Rays fine and few. Tracheids occasionally filled with resin relating to the durabihty ofthe wood. In general, the vjood of Glyptostrobus pensilis is a durable softwood with fine texture and therefore, the wood is valued for crafts and furnitures.
Keywords; Glyptosirobus pensilis, macroscopic features, microscopic features.
N g u o i phan bien Ngay nhan bai Ngay phan bien Ngay quyet dinh dang
TS. Vu Manh T u o n g 20/9/2014 15/10/2014 20/10/2014
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